The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has developed into an unprecedented global pandemic. Nucleoside analogs, such as Remdesivir and Favipiravir, can serve the first-line broad-spectrum antiviral drugs by targeting viral polymerases. However, underlying mechanisms for efficacies these are far from well understood. Here, we reveal that a pyrazine derivativ...

Triplex-forming oligonucleotides (TFOs) are powerful tools to interfere sequence-specifically with DNA-associated biological functions. (A/T,G)-containing TFOs are more commonly used in cells than (T,C)-containing TFOs, especially C-rich sequences; indeed the low intracellular stability of the non-covalent pyrimidine triplexes make the latter less active. In this work we studied the possibility...

Allopurinol ribonucleoside [4-hydroxy-1-P-D-ribofuranosylpyrazolo(3,4,-d)pyrimidine] was shown to be more effective than allopurinol in inhibiting the growth of Leishmania promastigotes in vitro. Both allopurinol and its ribonucleoside were equally effective in preventing the transformation of the intracellular form (amastigote) of Leishmania donovani to the extracellular form (promastigote). P...

The land 7-ribosyl 5’-phosphates of oxipurinol [4,6dihydroxypyrazolo(3,4 d)pyrimidine] were enzymatically synthesized. These nucleotides, 3-xanthosine S’-phosphate, and the 1-ribosyl 5’-phosphate of allopurinol [4-hydroxypyrazolo(3,4-d)pyrimidine] were characterized by spectral, chromatographic, and enzymatic procedures. The oxipurinol nucleotides were found to be potent competitive inhibitors ...

We present a computational study of the magnetic circular dichroism (MCD) spectra in the 200-300 nm wavelength region of purine and its derivative hypoxanthine, as well as of the pyrimidine bases of nucleic acids uracil, thymine, and cytosine, using the B3LYP and CAM-B3LYP functionals. Solvent effects are investigated within the polarizable continuum model and by inclusion of explicit water mol...

It has now been firmly established by several groups of workers (1-10) that in yeast thiamine is enzymatically synthesized from pyrimidine pyrophosphate and thiazole monophosphate. However, there is little information about the biosynthetic pathways of pyrimidine and thiazole themselves. Thiamine was found as the first natural com pound containing a thiazole ring. Recently, the presence of the ...

Protozoan parasites of the Leishmania genus express the metabolic machinery to synthesize pyrimidine nucleotides via both de novo and salvage pathways. To evaluate the relative contributions of pyrimidine biosynthesis and salvage to pyrimidine homeostasis in both life cycle stages of Leishmania donovani, individual mutant lines deficient in either carbamoyl phosphate synthetase (CPS), the first...

1. Abstract 2. Introduction 3. Purine and pyrimidine metabolism during somatic embryogenesis 3.1. Maintenance of embryogenic tissue 3.1.1. Purine metabolism during maintenance of embryogenic tissue 3.1.2. Pyrimidine metabolism during maintenance of embryogenic tissue 3.2. Development of somatic embryos 3.2.1. Purine metabolism during development of somatic embryos 3.2.2. Pyrimidine metabolism d...

Aim: To study the effect of new synthesized pyrimidine derivatives on growth Mycobacterium lufu ( M. ) and tuberculosis when cultivated Shkolnikova’s medium. Materials methods. The objects research were 6 samples - 5-(arylmethylidene)-2,4,6-pyrimidine-2,4,6(1 H ,3 ,5 )-trions under laboratory codes TAG1, TAG2, TAG3, TAG4, TAG5, TAG6 7 5-(getarylmethylidene)-2,4,6-pyrimidine-2,4,6(1 , 3 5 TAG7, ...